NHibernate mapping by code Map collection - nhibernate-mapping

Question

I'm moving from xml mapping to a code based mapping. There is a problem I'm experiencing with NHibernate Map collection.
Below is the xml mapping which perfectly works (it is a bit simplified, there is actually more properties and collections):
<class name="Company" where="IsDeleted=0" lazy="false">
<id name="Id">
<generator class="guid"></generator>
</id>
<map name="Contacts" lazy="true" cascade="all" where="IsDeleted=0">
<key column="CompanyId"></key>
<index column="Id" type="guid"></index>
<one-to-many class="CompanyContact"/>
</map>
</class>
The alternate code mapping I came up with is next:
public CompanyMap()
{
Id(x => x.Id, mapper => mapper.Generator(Generators.Guid));
Map(x => x.Contacts,
m =>
{
m.Where(FILTER);
m.Cascade(Cascade.All);
m.Lazy(CollectionLazy.Lazy);
m.Key(c => c.Column("CompanyId"));
}, k =>
{
k.Element(e =>
{
e.Column("Id");
});
k.OneToMany(e => e.Class(typeof(CompanyContact)));
});
}
The above generates next hbml for map:
<map name="Contacts" lazy="true" cascade="all" where="IsDeleted=0">
<key column="CompanyId" />
<map-key type="Guid" />
<one-to-many class="CompanyContact" />
</map>
I'm obviously lacking index column here. Therefore when generating SQL nhibernate will use the DefaultIndexColumnName which is idx.
So the question is how would I set the index for map?
Update:
According to hibernate documentation I should be using map-key.
So to rephrase the question, how would I set the column property of map-key?

Answer 1

This is not yet implemented for NHibernate version 3.3.1.
Created an issue in Jira for that.